Precautions for collecting stool occult blood test specimens: 1. The subject should avoid excessive consumption of iron or chlorophyll-rich foods, such as animal offal, red dates and spinach, 3 days before the test. The body will excrete iron from the body in the form of excreta after excessive intake, which will easily cause false positive test results. 2. Patients who need to take medications for a long time need to inform themselves in advance of the drug use before the test The patient who has been taking vitamin C, aspirin, and ibuprofen for a long time, as the drugs will affect the accuracy of their test results. 3, in the stool sampling process, try to choose the stool in the central part, and send the stool samples to the pathology laboratory as soon as possible to avoid contamination of stool samples.